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991.
Nakamura T Furukawa Y Nakagawa H Tsunoda T Ohigashi H Murata K Ishikawa O Ohgaki K Kashimura N Miyamoto M Hirano S Kondo S Katoh H Nakamura Y Katagiri T 《Oncogene》2004,23(13):2385-2400
To characterize molecular mechanism involved in pancreatic carcinogenesis, we analysed gene-expression profiles of 18 pancreatic tumors using a cDNA microarray representing 23,040 genes. As pancreatic ductal adenocarcinomas usually contain a low proportion of cancer cells in the tumor mass, we prepared 95% pure populations of pancreatic cancer cells by means of laser microbeam microdissection, and compared their expression profiles to those of similarly purified, normal pancreatic ductal cells. We identified 260 genes that were commonly upregulated and 346 genes that were downregulated in pancreatic cancer cells. Because of the high degree of purity in the cell populations, a large proportion of genes that we detected as upregulated or downregulated in pancreatic cancers were different from those reported in previous studies. Comparison of clinicopathological parameters with the expression profiles indicated that altered expression of 76 genes was associated with lymph-node metastasis and that of 168 genes with liver metastasis. In addition, expression levels of 30 genes were related to the recurrence of disease. These genome-wide expression profiles should provide useful information for finding candidate genes whose products might serve as specific tumor markers and/or as molecular targets for treatment of patients with pancreatic cancer. 相似文献
992.
993.
Tsuji A Tanabe M Onishi K Kitamura T Okinaka T Ito M Isaka N Nakano T 《Internal medicine (Tokyo, Japan)》2004,43(10):935-938
A 67-year-old woman with rheumatic aortic stenosis for 20 years was admitted to our hospital. Although she had no overt symptoms, she had severe aortic valve stenosis with a transvalvular pressure gradient of more than 150 mmHg. She had also been suffering from anemia and mild chronic renal failure. A peripheral blood smear showed numerous fragmented erythrocytes. Hemoglobin was 8.4 g/dl, lactate dehydrogenase was 316 IU/l, haptoglobin was less than 7.3 mg/dl, and hemosiderinuria was evident. We diagnosed intravascular hemolysis related to aortic stenosis. After we performed an aortic valve replacement, fragmentation on the peripheral blood smear dramatically disappeared. 相似文献
994.
Boffey J Nicholl D Wagner ER Townson K Goodyear C Furukawa K Furukawa K Conner J Willison HJ 《Journal of neuroimmunology》2004,152(1-2):98-111
In Guillain-Barré syndrome following Campylobacter enteritis, anti-lipopolysaccharide antibodies cross-react with neural gangliosides, thereby precipitating autoimmune neuropathy. We examined the properties of 15 murine anti-LPS/ganglioside mAbs specific for NeuAc(alpha2-8)NeuAc-Gal disialosyl epitopes. Many mAbs displayed features of an innate B cell origin including polyreactivity (13/15), hybridoma CD5 mRNA expression (5/15), predominance of IgM (9/15) or IgG3 (3/6) isotype, low affinity, and utilisation of unmutated VH and VL VDJ rearrangements. Antibody specificity resided in highly selective V gene usage, with 6/15 mAbs being encoded by the VH7183.3b gene. These data indicate that neuropathogenic antiganglioside autoantibodies can arise from the natural autoantibody repertoire. 相似文献
995.
Zhang R Tachibana T Takagi T Koutoku T Denbow DM Furuse M 《Behavioural brain research》2004,151(1-2):47-52
Glucagon-like peptide-1 (GLP-1) decreased corticotropin-releasing factor (CRF)-induced behaviors in neonatal chicks, and serotonin is one of the possible mechanisms through which GLP-1 affects CRF-induced behaviors. The present experiments were conducted to confirm the effect of serotonin on CRF-induced behaviors. In Experiment 1, chicks were intracerebroventricularly injected with either saline, 0.1 microg of CRF, 5.0 microg of serotonin, or 0.1 microg of CRF plus 5.0 microg of serotonin. Injection of CRF caused excitation as evidenced by increased spontaneous activities and distress vocalizations (DVs) compared to the control group. The effect of CRF was attenuated by serotonin since chicks became quiet after given CRF with serotonin. Sleep-like behaviors were observed in the serotonin group. The number of defecations was increased by CRF and decreased by serotonin. Both CRF and serotonin increased plasma corticosterone, and the effect was synergistic. Serotonin dose-dependently decreased locomotor activities of chicks after central administration of 0.1 microg of CRF, 0.1 microg of CRF plus 2.5, 5.0, or 10.0 microg of serotonin in Experiment 2. CRF-induced DVs were modified by serotonin. Instead of DVs, tender and low-pitched vocalizations were observed in chicks treated with CRF plus serotonin, the voice frequencies of which were less than 10 kHz. In conclusion, serotonin attenuated the CRF-induced behaviors while stimulating corticosterone release. These results indicate that the role of serotonin is dependent on the behaviors being measured. 相似文献
996.
Several pharmacological studies suggest the possible involvement of sigma(1) receptors in the pathogenesis of schizophrenia. An association has been reported between schizophrenia and two variants (GC-241-240TT and Gln2Pro) in the sigma(1) receptor gene (SIGMAR1). We also previously reported that, along with T-485 A, these two variants alter SIGMAR1 function. To investigate the role of SIGMAR1 in conveying susceptibility to schizophrenia, we performed a case-control study. We initially screened for polymorphisms in the SIGMAR1 coding region using PCR-single strand conformation polymorphism analysis. The distribution of SIGMAR1 polymorphisms was analyzed in 100 schizophrenic and 104 control subjects. A novel G620A variant was detected in exon4. G620A was predicted to alter the amino acid represented by codon 211 from arginine to glutamine. Our case-control study showed no significant association between the T-485 A, GC-241-240TT, Gln2Pro, and G620A (Arg211Gln) variants and schizophrenia and clinical characteristics. These findings suggest that these SIGMAR1 variants may not affect susceptibility to schizophrenia. 相似文献
997.
998.
Matsuzaki M Hasegawa T Takeda A Kikuchi A Furukawa K Kato Y Itoyama Y 《Brain research》2004,1004(1-2):83-90
alpha-Synuclein is a major component of intracytoplasmic inclusions including Lewy bodies (LB), Lewy neurites (LN) and glial cytoplasmic inclusions, and plays a key role in neurodegenerative processes in Parkinson's disease (PD) and other synucleinopathies. Although the molecular mechanisms of the disease process still remain to be elucidated, recent studies have suggested that an interaction between reactive oxygen species (ROS) and alpha-synuclein may be closely associated with the initiation and/or the progression of synucleinopathies. In this study, we established human dopaminergic SH-SY5Y cell lines overexpressing wild-type or mutant alpha-synuclein and exposed them to various ROS generators. After the exposure to ROS, alpha-synuclein aggregates were formed in the cytoplasm of these cells, and these were immunopositive for ubiquitin, nitrotyrosine and dityrosine, and positive for thioflavin S staining. Thus, the obtained cytoplasmic aggregates shared many features with inclusion bodies in synucleinopathies. The gamma-tubulin and molecular chaperones coexisted as well, suggesting that the aggregate formation is associated with the intracellular transport along microtubules and may reflect protective responses against neuronal insults. This cellular model not only will be informative for our understanding of the pathophysiological process in synucleinopathies, but also can be applied to the screening of neuroprotective molecules with therapeutic potential. 相似文献
999.
We have developed a Japanese version of the Depressive Experiences Questionnaire (DEQ), devised by Blatt et al., for assessing depression-prone personality and examined the questionnaire's reliability (test-retest reliability and internal consistency) and validity. To examine the questionnaire's validity, we evaluated its factorial validity and discriminant power for depression (i.e., construct validity). To test the construct validity of the DEQ with and without depression proneness, the scores on the DEQ subscales were compared between subjects with and without a lifetime history of major depressive disorder (MDD). The Inventory to Diagnose Depression, Lifetime version (IDDL), was used to identify lifetime depression. The reliability tests showed that the Japanese version has reliability almost similar to that of the original version. While the self-criticism has good reliability, the dependency appears to have only modest reliability. In the comparisons between subjects with and without lifetime histories of major depression, the former had significantly higher scores on the self-criticism dimension of the DEQ than did the latter, suggesting that the Japanese version of the DEQ, especially the self-criticism, may have the ability to distinguish individuals with lifetime depression from normal controls. We conclude that the DEQ is an acceptable instrument for assessing the depression-prone personality. 相似文献
1000.